Various types of ignition control apparatuses for internal combustion engines are proposed which are designed to stabilize a combustion state of an air-fuel mixture. For instance, Japanese Patent First Publication No. 2007-231927 discloses an ignition control apparatus which intermittently produces a plurality of discharges in one combustion stroke. Japanese Patent First Publication No. 2000-199470 teaches two ignition coils joined parallel to each other in order to secure a multiple discharge characteristic which provides a longer discharge duration. Japanese Patent First Publication No. 11-159427 discloses an ignition control apparatus which is capable of applying to a spark plug an auxiliary voltage developed by a DC/DC converter connected to a low voltage side of a secondary coil of an ignition coil in addition to voltage created by the secondary coil.